/****************************************************************************
 * Copyright 2010 Huascar A. Sanchez                                        *
 *                                                                          *
 * Licensed under the Apache License, Version 2.0 (the "License");          *
 * you may not use this file except in compliance with the License.         *
 * You may obtain a copy of the License at                                  *
 *                                                                          *
 *     http://www.apache.org/licenses/LICENSE-2.0                           *
 *                                                                          *
 * Unless required by applicable law or agreed to in writing, software      *
 * distributed under the License is distributed on an "AS IS" BASIS,        *
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
 * See the License for the specific language governing permissions and      *
 * limitations under the License.                                           *
 ****************************************************************************/
package com.gotobject.greatq.internal;

/**
 * very simple performance monitor
 * @author huascar.sanchez@gmail.com (Huascar A. Sanchez)
 */
public class Chronometer {
    private long start = System.currentTimeMillis();

    /**
     * resets and returns elapsed time in milliseconds.
     * @return elapsed time in milliseconds
     */
    public long reset() {
        long now = System.currentTimeMillis();
        try {
            return now - start;
        } finally {
            start = now;
        }
    }

    /**
     * Resets and logs elapsed time in milliseconds.
     * @param label
     *      measurement's intro label.
     */
    public void resetAndLog(String label) {
        System.out.println(label + ": " + reset() + "ms");
    }

}
